Modularizing Shiny app code

Hi,
I am struggling in this idea:
My ui.R
tabPanel("Access to Internet", icon = icon("list-ul"), value = "access",
introBox(
wellPanel(fluidRow( #Filter options
column(3,
p(tags$b("Step 1. Select group of interest.")),
selectInput("group", label = NULL, choices=group_list,
selected = "Parents")),
column(3,
tags$b("Step 2. Select question " )),
fluidRow(......), #Tab panel bracket

So I want user to make two selections between Parent-Child and then Question1, 2..
After this graphics should be generated based on selection.
How to modulize my app in order to keep both server.r and ui.r as simple as possible?
I read some sources online but still cannot advance
Thx